Journal of the American Chemical Society, Vol.137, No.16, 5284-5287, 2015
Lateral Growth of Composition Graded Atomic Layer MoS2(1-x)Se2x Nanosheets
Band gap engineering of transition-metal dichalcogenides is an important task for their applications in photonics, optoelectronics, and nanoelectronics. We report for the first time the continuous lateral growth of composition graded bilayer MoS2(1-x)Se2x alloys along single triangular nanosheets by an improved chemical vapor deposition approach. From the center to the edge of the nanosheet, the composition tail be gradually timed from x = 0 (pure MoS2) to x = 0.68, leading to the : corresponding bandgap being continuously Modulated from 1.82 eV (680 fun) to 1.64 eV (755 nm). Local photoluminescence scanning from the center to the edge gives single band edge emission peaks, indicating high : crystalline quality for the achieved alloy nanosheets,,which was further demonstrated by the microstructure characterizations. These novel 2D structures offer an interesting :system for probing the physical properties of layered materials and exploring new applications in functional nanoelectronic and optoelectronic devices.